Information processing system for relocating data and changing status information corresponding to the relocated data

An information storage system comprising:

• first non-volatile memory means for storing a plurality of sets of information;
• second non-volatile memory means, connected to said first non-volatile memory means, for storing a plurality of control information corresponding to the plurality of sets of information, respectively, the plurality of control information including respective status information and respective location information, wherein said first and second non-volatile memory means preserve stored information if an interruption in power supplied to the system occurs;
• work area preparing means, connected to said first non-volatile memory means, for preparing a work area succeeding a desired set of information to update the desired set of information by relocating a plurality of set of information succeeding the desired set of information to an area separate from an area of the desired set of information in said first non-volatile memory means, the relocating being performed by transferring the plurality of sets of information sequentially, one-by-one;
• and
• control means, connected to said second non-volatile memory means and said work area preparing means, for changing the status information corresponding to the one of the plurality of sets of information to be transferred, to indicate that the corresponding set of information is being transferred at the beginning of transfer, and for restoring the status information and updating the location information at the end of transfer,
• wherein said control means includes means for invalidating a set of information being transferred when the interruption of power supplied to the system occurs deleting control information including the status information indicating that the corresponding set of information is being transferred from said second non-volatile memory means when the system is started after the interruption of power supplied to the system.